As is known in the art of computer animation and modeling, the DECface.TM. product developed by Digital Equipment Corporation provides a talking synthetic face. The DECface.TM. talking synthetic face is a visual complement to the DECtalk.TM. product, a speech synthesizer also developed by Digital Equipment Corporation. By combining the audio functionality of a speech synthesizer with the graphical functionality of a computer generated talking synthetic face, a variety of engaging user interfaces can be provided. Examples include internet-based agents capable of seeking and retrieving documents on the world-wide web, avatars for chat applications, and front-end interfaces for kiosks.
A technique for adaptively synchronizing an audio signal of a speech synthesizer with a facial image being displayed is described by Waters et al. in U.S. Pat. No. 5,657,426, entitled Method and Apparatus for Producing Audio-Visual Synthetic Speech, issued Aug. 12, 1997, assigned to the assignee of the present application, and hereby incorporated herein by reference. Waters et al. disclose a speech synthesizer that generates fundamental speech units called phonemes, which are converted into audio signals. The phonemes are also converted into visual facial configurations called visemes (i.e., distinct mouth postures). The visemes are grouped into sequences of mouth gestures approximating the gestures of speech. The sequence of mouth gestures are then synchronized to the corresponding audio signals.
While Waters et al. provide a technique for synchronizing audio speech with visual mouth gestures, other gestures, such as those associated with eye and head movement, are not addressed. That is, Waters et al. do not address providing other gestures which typically accompany mouth gestures during speech.
Also, Waters et al. do not address providing gestures which are not associated with speech. That is, Waters et al. do not address providing other gestures, such as those associated with eye and head movement, which by themselves are often a means of communication.
In view of the foregoing, it is apparent that previously proposed techniques for providing a computer generated synthetic face do not provide certain features which would make the computer generated synthetic face more realistic. Accordingly, it would be desirable to provide a technique for providing a more realistic computer generated synthetic face.